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Which of the following electromagnetic waves has the longest wavelength?

1) Radio waves 2) Infrared radiations 3) x rays 4) visible rays Answer: Radio waves Solution: Radio waves have the longest wavelength... View Article

1) radiowaves and microwaves 2) ultraviolet rays and infrared rays 3) ultraviolet rays and x rays 4) infrared rays and microwaves... View Article

1) 10-8 m to 1015 m 2) 10-15 m to 108 m 3) 10-15 m to 1015 m 4) 108 m to 1015 m Answer: 2) 10-15 m to 108 m Solution:... View Article

1) radio waves 2) infrared rays 3) gamma rays 4) ultraviolet rays Answer: 3) gamma rays Solution: Gamma rays are used in medicine to... View Article

1) 5.77 x 10-8 Vm-1 2) 17.3 Vm-1 3) 57.7 x 10-8 Vm-1 4) 1.73 Vm-1 Answer: 2) 17.3 Vm-1 Solution: Intensity =... View Article

1) 3.6 x 108 m/s 2) 1.8 x 108 m/s 3) 1.8 x 106 m/s 4) 13.6 x 106 m/s Answer: 2) 1.8 x 108 m/s... View Article

1) 100km 2) 200km 3) 300km 4) 400km Answer: 3) 300km Solution: f = 1kilo cycles/s = 1 x 103 cycles/s = 103 Hz λ =... View Article

1) 36.6 m 2) 40.5 m 3) 42.3 m 4) 50.9 m Answer: 1) 36.6 m Solution: Wavelength, λ = c/ν = (3 x 108)/(8.2 ×... View Article

1) vmin ∝ V 2) vmin ∝ V1/2 3) vmin ∝ V-3 4) vmin ∝ V4 Answer: 1) vmin ∝... View Article

1) energy 2) velocity 3) wavelength 4) frequency Answer: 2) velocity Solution: All the components of the electromagnetic... View Article

1) radio waves 2) infrared waves 3) microwaves 4) γ – rays Answer: 1) radio waves Solution: The frequency 1057 MHz of... View Article

1) γ – rays 2) Visible light 3) Radio waves 4) Ultraviolet rays Answer:4) Ultraviolet rays Solution: Ultraviolet radiation is... View Article

1) 2 x 10-8 T 2) (1/2) x 10-8 T 3) 2 T 4) (1/2) T Answer: 1) 2 x 10-8 T Solution: The magnetic field, B = E/c = 6/(3 x 108)... View Article

1) 3 x 10-8 2) 3 x 10-6 3) 27 x 10-6 4) 27 x 1010 Answer: 2) 3 x 10-6 Solution: The maximum value of the magnetic field, B0 = E0/c =... View Article

1) for all wavelengths 2) in all media 3) for all intensities 4) for all frequencies Answer: 3) for all intensities Solution: c... View Article

1) √IrK 2) √IrE0 3) √I0E0 4) 1/√IrK Answer: 1) √IrK Solution: Refractive index, n =... View Article

1) P = 0, E ≠ 0 2) P ≠ 0, E = 0 3) P ≠ 0, E ≠ 0 4) P = 0, E = 0 Answer: 3) P ≠... View Article

1) v = 1/√μrK 2) v = c √μrK 3) v = c/√μrK 4) v = k √μrc Answer: v = c √μrK... View Article

1) 5.5 x 10-12 J 2) 1.1 x 10-11 J 3) 2.2 x 10-11 J 4) 1.65 x 10-11 J Answer: 2) 1.1 x 10-11 J Solution: E = 50 sin ω... View Article

1) 2 × 10-8 2) 3 × 10-7 3) 6 × 10-8 4) 5 × 10-7 Answer: 1) 2 × 10-8 Solution: Electric and magnetic fields are... View Article